SECTION AIR COILS

Transcription

1 SECTION PART 1 - GENERAL 1.1 DESCRIPTION SPEC WRITER NOTES: 1. Use this section only for NCA projects. 2. Delete between // // if not applicable to project. Also delete any other item or paragraph not applicable in the section and renumber the paragraphs. 3. Coordinate VA standard details with this spec Section and show details on H and P drawings as applicable: a Water Coils-Piping Connections A. This Section specifies heating and cooling coils for air handling units and duct applications. B. A complete listing of common acronyms and abbreviations are included in Section , COMMON WORK RESULTS FOR HVAC. 1.2 RELATED WORK SPEC WRITER NOTE: Retain one of two paragraphs below. A. //Section , GENERAL REQUIREMENTS (Major NCA Projects).// B. //Section , GENERAL REQUIREMENTS (Minor NCA Projects).// C. Section , SHOP DRAWINGS, PRODUCT DATA, AND SAMPLES. D. Section , REFERENCE STANDARDS. E. Section , SUSTAINABLE DESIGN REQUIREMENTS. F. //Section GENERAL COMMISSIONING REQUIREMENTS.// G. Section , COMMON WORK RESULTS FOR HVAC: General mechanical requirements and items which are common to more than one section of Division 23. H. //Section , COMMISSIONING OF HVAC SYSTEMS.// I. Section , DIRECT-DIGITAL CONTROL SYSTEM FOR HVAC. 1.3 APPLICABLE PUBLICATIONS SPEC WRITER NOTE: Make material requirements agree with requirements specified in the referenced Applicable Publications. Verify and update the publication list to that which applies to the project, unless the reference applies to all mechanical systems. Publications that apply to all mechanical systems may not be specifically referenced in the

2 body of the specification, but, shall form a part of this specification. A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by the basic designation only. B. Air Conditioning, Heating, and Refrigeration Institute (AHRI): Forced-Circulation Air-Cooling Air-Heating Coils C. American Society for Testing and Materials (ASTM): B75/75M Standard Specification for Seamless Copper Tube D. National Electric Manufacturers Association (NEMA): Enclosures for Electrical Equipment (1,000 Volts Maximum) E. National Fire Protection Association (NFPA): National Electric Code F. Underwriters Laboratories, Inc. (UL): (R2014)...Standard for Electric Duct Heaters 1.4 SUBMITTALS A. Submittals, including number of required copies, shall be submitted in accordance with Section , SHOP DRAWINGS, PRODUCT DATA, AND SAMPLES. B. Information and material submitted under this section shall be marked SUBMITTED UNDER SECTION ,, with applicable paragraph identification. C. Manufacturer's Literature and Data for Heating and Cooling Coils including: Full item description and optional features and accessories. Include dimensions, weights, materials, applications, standard compliance, model numbers, size, and capacity. 1. Submit type, size, arrangements and performance details. Present application ratings in the form of tables, charts or curves. D. Complete operating and maintenance manuals including wiring diagrams, technical data sheets, information for ordering replacement parts, and troubleshooting guide: 1. Include complete list indicating all components of the systems. 2. Include complete diagrams of the internal wiring for each item of equipment. 3. Diagrams shall have their terminals identified to facilitate installation, operation and maintenance

3 E. //Completed System Readiness Checklist provided by the Commissioning Agent and completed by the contractor, signed by a qualified technician and dated on the date of completion, in accordance with the requirements of Section , COMMISSIONING OF HVAC SYSTEMS.// F. //Submit training plans and instructor qualifications in accordance with the requirements of Section , COMMISSIONING OF HVAC SYSTEMS.// 1.5 QUALITY ASSURANCE A. Refer to paragraph, QUALITY ASSURANCE, Section , COMMON WORK RESULTS FOR HVAC. B. Unless specifically exempted by these specifications, heating and cooling coils shall be tested, rated, and certified in accordance with AHRI 410 and shall bear the AHRI certification label. 1.6 AS-BUILT DOCUMENTATION SPEC WRITER NOTE: Coordinate O&M Manual requirements with Section , GENERAL REQUIREMENTS (Major NCA Projects) or Section , GENERAL REQUIREMENTS (Minor NCA Projects). O&M manuals shall be submitted for content review as part of the close-out documents. A. Submit manufacturer s literature and data updated to include submittal review comments and any equipment substitutions. B. Submit operation and maintenance data updated to include submittal review comments, substitutions and construction revisions shall be //in electronic version on CD or DVD// inserted into a three ring binder. All aspects of system operation and maintenance procedures, including applicable piping isometrics, wiring diagrams of all circuits, a written description of system design, control logic, and sequence of operation shall be included in the operation and maintenance manual. The operations and maintenance manual shall include troubleshooting techniques and procedures for emergency situations. Notes on all special systems or devices shall be included. A List of recommended spare parts (manufacturer, model number, and quantity) shall be furnished. Information explaining any special knowledge or tools the owner will be required to employ shall be inserted into the As-Built documentation. C. The installing contractor shall maintain as-built drawings of each completed phase for verification; and, shall provide the complete set at the time of final systems certification testing. As-built drawings

4 are to be provided, and a copy of them in Auto-CAD version // // provided on CD or DVD. Should the installing contractor engage the testing company to provide as-built or any portion thereof, it shall not be deemed a conflict of interest or breach of the third party testing company requirement. D. Certification documentation shall be provided to COR 10 working days prior to submitting the request for final inspection. The documentation shall include all test results, the names of individuals performing work for the testing agency on this project, detailed procedures followed for all tests, and certification that all results of tests were within limits specified. PART 2 - PRODUCTS 2.1 HEATING AND COOLING COILS A. Conform to ASTM B75/B75M and AHRI 410. B. Tubes: Minimum 18 mm (5/8 inch) tube diameter; Seamless copper tubing. C. Fins: mm ( inch) aluminum or mm ( inch) copper mechanically bonded or soldered or helically wound around tubing. Fin spacing of 2.6 through 4.7 fins per cm (80 through 144 fins per foot). D. Headers: Copper, welded steel or cast iron. Provide seamless copper tubing or resistance welded steel tube for volatile refrigerant coils. E. "U" Bends, Where Used: Machine die-formed, silver brazed to tube ends. F. Coil Casing: 1.6 mm (16 gage) galvanized steel with tube supports at 1200 mm (48 inch) maximum spacing. Construct casing to eliminate air bypass and moisture carry-over. Provide duct connection flanges. G. Pressures kpa (psig): Press Water Coil kpa (psig) Refrigerant Coil kpa (psig) Test 2070 (300) 2070 (300) Working 1380 (200) 1725 (250) H. Protection: Unless protected by the coil casing, provide cardboard, plywood, or plastic material at the factory to protect tube and finned surfaces during shipping and construction activities. I. Vents and Drain: Coils that are not vented or drainable by the piping system shall have capped vent/drain connections extended through coil casing

5 2.2 WATER COILS, INCLUDING PROPYLENE GLYCOL-WATER A. Drainable Type (Self-Draining, Self-Venting); manufacturer standard: 1. Cooling, all types. 2. Runaround energy recovery. B. //Cleanable Tube Type: manufacturers standard. 1. Waste water applications.// 2.3 VOLATILE REFRIGERANT COILS A. Continuous circuit, straight tubes, dry expansion type equipped with multi-port distribution header, less expansion valve. B. Minimum 18 mm (5/8 inch) tube diameter. C. Designed for CFC or HCFC free refrigerants. 2.4 ELECTRIC HEATING COILS A. Standards: Electric coils shall meet the requirements of NFPA 70 and UL B. General: Aluminized steel frame, spot welded. Duct mounted units may be flanged or slip-in design with built-in terminal box completely factory wired to terminals. Control panels for coils in air handling units may be built-in or remote in NEMA 250, Type l enclosure. C. Coils: Open type, 80 percent nickel, 20 percent chromium resistance wire, insulated by floating ceramic bushings and supported in aluminized steel brackets spaced on 100 mm (4 inch) maximum centers. Coils shall be mechanically crimped in stainless steel terminals which are insulated from the frame with high temperature molded phenolic bushings. D. Over Temperature Protection: 1. Primary system: Automatic reset thermal cutout. 2. Secondary system: Load-carrying manual reset thermal cutout factory wired in series with each heater stage. E. Overcurrent Protection: Comply with UL and NEC. SPEC WRITER NOTE: Specify mercury type contactors when quiet operation (reheat coil above ceiling) is required. F. Contactors: Disconnecting magnetic type (when required), except for duct mounted reheat coils contactors provide disconnecting mercury type. G. Airflow Interlock: Diaphragm operated differential airflow pressure switch. SPEC WRITER NOTE: Verify that temperature controls are shown on the drawings

6 Include these temperature controls in Section , DIRECT-DIGITAL CONTROL SYSTEM FOR HVAC. H. Leaving air temperature control for electric coils mounted in air handling units shall be //3// //6// //10// //18// step control driven by a unit mounted modulating thermostat. 2.5 SILICON-CONTROLLED RECTIFIER CONTROL SYSTEM A. Provide control of power to unit by a UL-listed solid-state siliconcontrolled rectifier (SCR) system such that voltage is continuously impressed and varied in minute increments over a range of zero to rated voltage or to 105 percent of rated voltage maximum. PART 3 - EXECUTION 3.1 INSTALLATION A. If an installation is unsatisfactory to the COR, the Contractor shall correct the installation at no additional cost or time to the Government. B. Follow coil manufacturer's instructions for handling, cleaning, installation and piping connections. C. Comb fins, if damaged. Eliminate air bypass or leakage at coil sections. 3.2 STARTUP AND TESTING A. Make tests as recommended by product manufacturer and listed standards and under actual or simulated operating conditions and prove full compliance with design and specified requirements. Tests of the various items of equipment shall be performed simultaneously with the system of which each item is an integral part. B. When any defects are detected, correct defects and repeat test at no additional cost or time to the Government. C. //The Commissioning Agent will observe startup and contractor testing of selected equipment. Coordinate the startup and contractor testing schedules with the COR and Commissioning Agent. Provide a minimum notice of 10 working days prior to startup and testing.// 3.3 //COMMISSIONING A. Provide commissioning documentation in accordance with the requirements of Section , COMMISSIONING OF HVAC SYSTEMS. B. Components provided under this section of the specification will be tested as part of a larger system.//

7 3.4 DEMONSTRATION AND TRAINING A. Provide services of manufacturer s technical representative for //four// // // hour//s// to instruct each VA personnel responsible in the operation and maintenance of units. B. //Submit training plans and instructor qualifications in accordance with the requirements of Section , COMMISSIONING OF HVAC SYSTEMS.// E N D